Groundsmaster 4300--DPage 5 -- 30Electrical System
Parking Brake Switch
The parking brake switch is a normally open proximity
switch. The parking brake switch is attached to the bot-
tom of the brake pedal (Fig. 32). The parking brake
switch is used as an input for the TEC controller.
Whentheparkingbrake is not applied, the parking brake
detent is positioned near the target end of the parking
brake switch so the switch is closed. The parking brake
detent is moved away from the switch when the parking
brake is applied causing the switch to open.
Testing
1. Before disconnecting the parking brake switch for
testing, the switch and its circuit wiring should be tested
as a TEC controller input with the Diagnostic Display
(see Diagnostic Display in the Troubleshooting section
of this chapter).If theDiagnostic Displayverifies that the
parking brake switch and circuit wiring are functioning
correctly, no further switch testing is necessary. If, how-
ever,theDiagnostic Display determinesthat theparking
brake switch and circuit w iring are not functioning cor-
rectly, proceed with testing procedure.
2. Turn ignition switch to the ON position (do not start
engine) and check LED on cable end of brake switch
(Fig. 32). LED should be illuminated when the parking
brake is not applied.
3. With the ignition switch still in the ON position (do not
start engine), apply parking brake and check LED on
cable end of parking brake switch. LED should not be
illuminated when the parking brake is applied.
4. If the brake switch LED did not function correctly:
A. Make sure that brake switch is properly adjusted
(see Parking Brake Switch in the Adjustments sec-
tion of this chapter). If necessary, adjust switch and
return to step 2 above.
B. Make sure ignition switch is OFF and disconnect
the parking brake switch connector from the ma-
chine wire harness.
C. Verify that the machine wire harness connector
terminal for black wire is closed (continuity) to
ground.
D. Turn ignition switch to the ON position (do not
start engine) and verify with a multimeter that ma-
chine wire harness connector terminal for pink wire
has system voltage (12 VDC) present.
E. If black wire is closed to ground, pink wire has
system voltage present and switch LED did not func-
tion, replace parking brake switch. Adjust switch af-
ter installation (see Parking Brake Switch in the
Adjustments section of this chapter).
5. If the parking brake switch tests correctly and a cir-
cuit problem still exists, check wire harness (see Electri-
cal Schematic and Circuit Drawings in Chapter 8 --
Foldout Drawings).
6. Make sure that parking brake switch is connected to
wire harness when testing is complete.
1. Parking brake switch
2. Lock washer (2 used)
3. Jam nut (2 used)
4. Parking brake detent
5. Brake pedal
6. Switch LED location
Figure 32
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3
4
5
1
2
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